1. Field of the Invention
This invention relates to underwater trusses for breakwater structures, and more particularly to underwater trusses of three-dimensional structure adapted to be used as a breakwater or an underwater structure for protecting an underwater construction from impact of waves.
The underwater trusses in accordance with the present invention is particularly applicable to the construction of large-scale trusses on the bottom of the sea which serves as fishing grounds or an underwater nursery for culturing pearls or marine plants as well as a breakwater.
2. Description of the Prior Art
It has been known in the art to accumulate concrete blocks in the water to break waves. However, the concrete blocks are very difficult to handle and the work to accumulate them on the bottom of the sea needs a great labor. Therefore, it is practically uneconomical to build up a breakwater by use of concrete blocks. Further, the height of the breakwater structure built up by use of the concrete blocks is limited to about 15m.
In order to provide a new underwater construction which is free from the above described defects inherent in the structure made of concrete blocks, it has been known to build up underwater trusses composed of hollow webs and joint members as disclosed in U.S. Pat. No. 3,864,049 patented to the present inventor.